bluray: Don't fail silently.

(cherry picked from commit db56ab24bcd6319316fc1d0308ed28b66a8d5477)
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

modules/access/bluray.c

@@ -262,8 +262,10 @@ static int blurayOpen( vlc_object_t *object )
     p_sys->b_menu = var_InheritBool(p_demux, "bluray-menu");
     if (p_sys->b_menu) {
         p_sys->p_input = demux_GetParentInput(p_demux);
-        if (unlikely(!p_sys->p_input))
+        if (unlikely(!p_sys->p_input)) {
+            error_msg = "Could not get parent input";
             goto error;
+        }
 
         /* libbluray will start playback from "First-Title" title */
         if (bd_play(p_sys->bluray) == 0) {